keras model structure visualization - tensorflow

I want to see keras model like this. I used K.get_session().graph and get
tensorflow.python.framework.ops.Graph at 0x7f2a8b809400
but i to see this graph and save it. I am using tensorflow backend

Install tensorboard
Import it
from keras.callbacks import TensorBoard
Load it into a variable
tbCallBack = TensorBoard(log_dir='Graph',
histogram_freq=10,
write_graph=True,
write_images=True)
And then use that as a callback at training:
model.fit(x, y, ...
callbacks=[tbCallBack])
Make sure you have a made a directory called 'Graph' or whatever you want. Then before training run in terminal:
tensorboard --logdir Graph
And then you can see your graph in your browser

Related

How to visualize tf.compat.v1 static graph in tensorboard?

For a given graph, how can we visualize the graph using tensorboard for tf.compat.v1 ?
Sharing this here after searching everywhere. Most of the documentations explains tf.keras and not for tf.compat.v1 static graphs
First export the graph to a logdir that tensorboard can use!
import tensorflow as tf
# Get the default graph
graph = tf.compat.v1.get_default_graph()
writer = tf.compat.v1.summary.FileWriter("logs", graph)
After that simply open tensorboard in the specified directory (here logs/)
python -m tensorboard.main --logdir logs/

View logs from Keras Tuner in Tensorboard

I am tuning a Neural Net with Keras Tuner
I am creating logs this way:
tuner = RandomSearch(
build_model,
objective='val_accuracy',
max_trials=5,
executions_per_trial=3,
directory='my_dir',
project_name='helloworld')
This gives me this directory of log files:
/my_dir/helloworld/
-trial_xxxxx
-trial_yyyy
-trial_zzzz
-oracle.json
-tuner0.json
I can get the summary by writing
tuner.result_summary()
or even get the best model using
tuner.get_best_models(num_models=1)[0]
But I also want to explore the runs more in details and see if there are any patterns. For that I want to use TensorBoard, but if I write:
%tensorboard --logdir="my_dir/helloworld"
I only get a empty TensorBoard. I guess the problem here is that Keras Tuner and TensorBoard write logs in different fileformat.
My question is stil have anyone been able to run hyperparameter optimalization in Keras Tuner and then watch the log files in TensorBoard afterwards?
Tensorboard needs seperate logging through callbacks:
before running tuner.search() add
tensorboard=TensorBoard(log_dir='tensorborad_log_dir')
and add the tensorboard callback to tuner.search()
tuner.search(X_train, y_train, callbacks=[tensorboard])
then you can run
%tensorboard --logdir='tensorborad_log_dir'

how to properly saving loaded h5 model to pb with TF2

I load a saved h5 model and want to save the model as pb.
The model is saved during training with the tf.keras.callbacks.ModelCheckpoint callback function.
TF version: 2.0.0a
edit: same issue also with 2.0.0-beta1
My steps to save a pb:
I first set K.set_learning_phase(0)
then I load the model with tf.keras.models.load_model
Then, I define the freeze_session() function.
(optional I compile the model)
Then using the freeze_session() function with tf.keras.backend.get_session
The error I get, with and without compiling:
AttributeError: module 'tensorflow.python.keras.api._v2.keras.backend'
has no attribute 'get_session'
My Question:
Does TF2 not have the get_session anymore?
(I know that tf.contrib.saved_model.save_keras_model does not exist anymore and I also tried tf.saved_model.save which not really worked)
Or does get_session only work when I actually train the model and just loading the h5 does not work
Edit: Also with a freshly trained session, no get_session is available.
If so, how would I go about to convert the h5 without training to pb? Is there a good tutorial?
Thank you for your help
update:
Since the official release of TF2.x graph/session concept has changed. The savedmodel api should be used.
You can use the tf.compat.v1.disable_eager_execution() with TF2.x and it will result in a pb file. However, I am not sure what kind of pb file type it is, as saved model composition changed from TF1 to TF2. I will keep digging.
I do save the model to pb from h5 model:
import logging
import tensorflow as tf
from tensorflow.compat.v1 import graph_util
from tensorflow.python.keras import backend as K
from tensorflow import keras
# necessary !!!
tf.compat.v1.disable_eager_execution()
h5_path = '/path/to/model.h5'
model = keras.models.load_model(h5_path)
model.summary()
# save pb
with K.get_session() as sess:
output_names = [out.op.name for out in model.outputs]
input_graph_def = sess.graph.as_graph_def()
for node in input_graph_def.node:
node.device = ""
graph = graph_util.remove_training_nodes(input_graph_def)
graph_frozen = graph_util.convert_variables_to_constants(sess, graph, output_names)
tf.io.write_graph(graph_frozen, '/path/to/pb/model.pb', as_text=False)
logging.info("save pb successfully!")
I use TF2 to convert model like:
pass keras.callbacks.ModelCheckpoint(save_weights_only=True) to model.fit and save checkpoint while training;
After training, self.model.load_weights(self.checkpoint_path) load checkpoint;
self.model.save(h5_path, overwrite=True, include_optimizer=False) save as h5;
convert h5 to pb just like above;
I'm wondering the same thing, as I'm trying to use get_session() and set_session() to free up GPU memory. These functions seem to be missing and aren't in the TF2.0 Keras documentation. I imagine it has something to do with Tensorflow's switch to eager execution, as direct session access is no longer required.
use
from tensorflow.compat.v1.keras.backend import get_session
in keras 2 & tensorflow 2.2
then call
import logging
import tensorflow as tf
from tensorflow.compat.v1 import graph_util
from tensorflow.python.keras import backend as K
from tensorflow import keras
from tensorflow.compat.v1.keras.backend import get_session
# necessary !!!
tf.compat.v1.disable_eager_execution()
h5_path = '/path/to/model.h5'
model = keras.models.load_model(h5_path)
model.summary()
# save pb
with get_session() as sess:
output_names = [out.op.name for out in model.outputs]
input_graph_def = sess.graph.as_graph_def()
for node in input_graph_def.node:
node.device = ""
graph = graph_util.remove_training_nodes(input_graph_def)
graph_frozen = graph_util.convert_variables_to_constants(sess, graph, output_names)
tf.io.write_graph(graph_frozen, '/path/to/pb/model.pb', as_text=False)
logging.info("save pb successfully!")

Keras model to tensforflow

Is it possible to convert a keras model (h5 file of network architecture and weights) into a tensorflow model? Or is there an equivalent function to model.save of keras in tensorflow?
Yes, it is possible, because Keras, since it uses Tensorflow as backend, also builds computational graph. You just need to get this graph from your Keras model.
"Keras only uses one graph and one session. You can access the session
via: K.get_session(). The graph associated with it would then be:
K.get_session().graph."
(from fchollet: https://github.com/keras-team/keras/issues/3223#issuecomment-232745857)
Or you can save this graph in checkpoint format (https://www.tensorflow.org/api_docs/python/tf/train/Saver):
import tensorflow as tf
from keras import backend as K
saver = tf.train.Saver()
sess = K.get_session()
retval = saver.save(sess, ckpt_model_name)
By the way, since tensorflow 13 you can use keras right from it:
from tensorflow.python.keras import models, layers

How can I convert a trained Tensorflow model to Keras?

I have a trained Tensorflow model and weights vector which have been exported to protobuf and weights files respectively.
How can I convert these to JSON or YAML and HDF5 files which can be used by Keras?
I have the code for the Tensorflow model, so it would also be acceptable to convert the tf.Session to a keras model and save that in code.
I think the callback in keras is also a solution.
The ckpt file can be saved by TF with:
saver = tf.train.Saver()
saver.save(sess, checkpoint_name)
and to load checkpoint in Keras, you need a callback class as follow:
class RestoreCkptCallback(keras.callbacks.Callback):
def __init__(self, pretrained_file):
self.pretrained_file = pretrained_file
self.sess = keras.backend.get_session()
self.saver = tf.train.Saver()
def on_train_begin(self, logs=None):
if self.pretrian_model_path:
self.saver.restore(self.sess, self.pretrian_model_path)
print('load weights: OK.')
Then in your keras script:
model.compile(loss='categorical_crossentropy', optimizer='rmsprop')
restore_ckpt_callback = RestoreCkptCallback(pretrian_model_path='./XXXX.ckpt')
model.fit(x_train, y_train, batch_size=128, epochs=20, callbacks=[restore_ckpt_callback])
That will be fine.
I think it is easy to implement and hope it helps.
Francois Chollet, the creator of keras, stated in 04/2017 "you cannot turn an arbitrary TensorFlow checkpoint into a Keras model. What you can do, however, is build an equivalent Keras model then load into this Keras model the weights"
, see https://github.com/keras-team/keras/issues/5273 . To my knowledge this hasn't changed.
A small example:
First, you can extract the weights of a tensorflow checkpoint like this
PATH_REL_META = r'checkpoint1.meta'
# start tensorflow session
with tf.Session() as sess:
# import graph
saver = tf.train.import_meta_graph(PATH_REL_META)
# load weights for graph
saver.restore(sess, PATH_REL_META[:-5])
# get all global variables (including model variables)
vars_global = tf.global_variables()
# get their name and value and put them into dictionary
sess.as_default()
model_vars = {}
for var in vars_global:
try:
model_vars[var.name] = var.eval()
except:
print("For var={}, an exception occurred".format(var.name))
It might also be of use to export the tensorflow model for use in tensorboard, see https://stackoverflow.com/a/43569991/2135504
Second, you build you keras model as usually and finalize it by "model.compile". Pay attention that you need to give you define each layer by name and add it to the model after that, e.g.
layer_1 = keras.layers.Conv2D(6, (7,7), activation='relu', input_shape=(48,48,1))
net.add(layer_1)
...
net.compile(...)
Third, you can set the weights with the tensorflow values, e.g.
layer_1.set_weights([model_vars['conv7x7x1_1/kernel:0'], model_vars['conv7x7x1_1/bias:0']])
Currently, there is no direct in-built support in Tensorflow or Keras to convert the frozen model or the checkpoint file to hdf5 format.
But since you have mentioned that you have the code of Tensorflow model, you will have to rewrite that model's code in Keras. Then, you will have to read the values of your variables from the checkpoint file and assign it to Keras model using layer.load_weights(weights) method.
More than this methodology, I would suggest to you to do the training directly in Keras as it claimed that Keras' optimizers are 5-10% times faster than Tensorflow's optimizers. Other way is to write your code in Tensorflow with tf.contrib.keras module and save the file directly in hdf5 format.
Unsure if this is what you are looking for, but I happened to just do the same with the newly released keras support in TF 1.2. You can find more on the API here: https://www.tensorflow.org/api_docs/python/tf/contrib/keras
To save you a little time, I also found that I had to include keras modules as shown below with the additional python.keras appended to what is shown in the API docs.
from tensorflow.contrib.keras.python.keras.models import Sequential
Hope that helps get you where you want to go. Essentially once integrated in, you then just handle your model/weight export as usual.